Question 12.2

A 62-year-old patient has been admitted to your ICU for routine post-operative monitoring after a vascular surgical procedure.

The pre-operative full blood count (FBC) is displayed below:

Parameter

Patient Value     

Adult Normal Range

Haemoglobin

125 g/L*

130-180

White Cell Count

7.4 x 109/L

4.5-11

Platelets

255 x 109/L

150-400

Mean Cell Volume

110 fL*

80-98

Mean Cell Haemoglobin

30 pg/cell

27-33

Mean Cell Haemoglobin Concentration        

320 p/L

310-360

12.2.1    List six possible causes for the findings on the FBC.    (3 marks)

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College Answer

Syllabus topic/section:
2.1.21 Applied Pharmacology in Intensive Care.
Aim:
To allow the candidate to demonstrate competency in data interpretation.
Discussion:
Candidates generally did extremely well in this repeat data question. Candidates are reminded that if the question asks you to list 6 causes there are only marks for 6 answers. If 8 are written the top 6 will be assessed and the bottom 2 causes will not be marked.

Discussion

This is a repeat of Question 25.2 from the second paper of 2020.

The abnormalities are:

  • A slightly anaemic haemoglobin, for a dude
  • A wildly elevated mean cell volume (i.e. macrocytosis)

The cell haemoglobin content is normal, i.e. this is a macrocytic normochromic anaemia.

There are several common causes:

  • Alcoholism
  • Vitamin B12 deficiency
  • Folate deficiency
  • Myelodysplastic syndromes 

There are also a few uncommon causes:

  • Reticulocytosis
  • Nonalcoholic and alcoholic liver disease
  • Hypothyroidism
  • Multiple myeloma
  • Aplastic anemia
  • Acute leukemia
  • Drugs:
    • trimethoprim, triamterine, nitrous oxide, phenytoin, valproate, chemotherapy agents, HIV antiretrovirals and metformin.

References

Aslinia, Florence, Joseph J. Mazza, and Steven H. Yale. "Megaloblastic anemia and other causes of macrocytosis." Clinical medicine & research 4.3 (2006): 236-241.

Walker, H. Kenneth, et al. "Peripheral blood smear." (1990). in Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition.